No abstract available

No abstract available

[en] Ferrokinetic parameters were evaluated with ⁵⁹Fe and red-cell survival with ⁵¹Cr by classical techniques in a total of 17 patients with sickle-cell disease. The mean plasma ⁵⁹Fe half-disappearance time in these patients was 29.5 min as compared with a normal value of 92 min, and the t1/2 ⁵¹Cr 8.0 days as compared with a normal value of 26.0 days. The mean red-cell iron turnover rate was elevated to 9 times normal. The increased destruction of red cells appeared to take place predominantly, though not entirely, in the spleen. Eight of the 17 patients studied were identified as having intercurrent complications, but these did not significantly affect the results of the investigations. A group of 5 boys in whom the red-cell iron turnover rate was elevated to a lesser degree than in the other patients were subjected to more detailed studies of plasma ⁵⁹Fe clearance with particular reference to ineffective erythropoiesis. In these patients, the plasma ⁵⁹Fe clearance curves showed precocious humps characteristic of ineffective erythropoiesis. Detailed analysis of the results indicated ineffective erythropoiesis corresponding to 3.6, 16.0, 22.6, 32.0 and 50.0 % of the iron initially taken up by the bone marrow. It is concluded that while the anaemia in most patients with sickle-cell disease is mainly due to shortened survival of the circulating red cells, with increased destruction of red cells in the spleen, ineffective erythropoiesis may none the less be an important factor determining the actual degree of this anaemia

[en] A radioisotopic measuring method developed for studying the wear process of wheel rims of railway vehicles is described. The wear process may be monitored by the measurement of activity of a thin galvanic layer deposited onto the rim and labelled by iron 59. The high sensitivity of the method allows the determination of the wear rate distribution even within a few days. The results of measurements on three different rim profiles are analysed. (R.J.)

[en] Erythroblastopenia is probably not rare in chronic lymphocytic leukemia (CLL) but the diagnosis could be difficult. It produces a severe and rapidly developing anemia, without evidence of hemolysis. The chief differential diagnosis is the common bone marrow insufficiency of end-stage CLL. Iron kinetics measurements are typical, showing a total erythropoietic insufficiency, and a red cell utilization of radio-iron that is practically zero. Erythroblastopenia could be cured with corticosteroid or sometimes with immunosuppressive treatment

No abstract available

[en] The distribution of iron-59 in blood at various time intervals was studied in sham and partially-hepatectomized rats after a single intravenous injection of ⁵⁹Fe (III) citrate. A significant difference was observed in the rate of disappearance and reappearance of iron-59 in circulation. Administration of cadmium and manganese at a concentration of 0.5 and 2 mg/kg b. wt., respectively, did not cause any significant change in this pattern. A significant decrease in iron-59 incorporation in the liver of hepatectomized rat was produced by cadmium while manganese had no effect. (author)

[en] Eight patients presenting primary myelofibrosis or spent polycythemia were submitted to a ferrokinetic study, a trephine bone marrow biopsy and a bone marrow puncture. In all cases before treatment (splenic radiotherapy) ferrokinetic measurements demonstrated an ineffective erythropoiesis, the intensity of which was precised on bone marrow biopsies, in numbering the erythroblasts per surface unit. Bone marrow biopsies permitted also, through a semiquantitative estimate of the bone marrow cellularity, to evaluate an aplasia component not always expected with ferrokinetic study. Study of bone marrow allowed to precise the site of the erythroblastic abortion, cellular death might occur during the last mitosis of the erythroblastic series (transition from the polychromatophil erythroblasts to the acidophil erythroblasts). In order to delineate the general pattern of erythropoiesis before treatment and when assessing the results of a treatment, besides ferrokinetic measurements, the study of bone marrow biopsy and smears appears relevant

[en] Hemin was found to enhance the growth of murine erythroid colonies in culture. In the presence of 100 mU/ml erythropoietin (EPO), the addition of hemin (0.05-0.2 mM) resulted in the growth of twice as many colonies as were obtained with EPO alone. Hemin also significantly increased erythroid colony formation in culture in the absence of added EPO. Hemoblobin synthesis as measured by the incorporation of ⁵⁹Fe into cyclohexanone extractable heme was augmented in culture by hemin. Neither Δ-aminolevulinic acid, a hemin precursor, nor FeCl₃ increased colony number. (author)

[en] A brief description is presented of the method of measuring diffusion characteristics of elements in solid metals and their alloys, based on the use of radioisotopes. (author). 4 figs., 13 refs